Why do we use nested message send for alloc in object-c?

Question

For allocation and initialization to a class, we do

Party *partyInstance = [Party alloc];
[partyInstance init];

or

Party *partyInstance = [[Party alloc] init];

Is there any special reason to use nested message? Or is it just for convenience?

just convenience. It is used so often that there is no "understanding" benefit to splitting it into two lines — Ben, Nov 26 '14 at 18:18
@Ben: No. The first version is *wrong* because `init` might return a object which is different to the one being passed. — Martin R, Nov 26 '14 at 18:21

score 3 · Accepted Answer · answered Nov 26 '14 at 18:20

3

Yes, there is. You need to assign to your object the return value of init, not that of alloc (because of class clusters). And writing

Party *partyInstance = [Party alloc];
partyInstance = [partyInstance init];

would be quite awkward.

answered Nov 26 '14 at 18:20

1 Answers1